Extracapsular Axillary Nodal Extension (ECE) in Breast Cancer: Patterns of Recurrence, Arm Edema, and Survival after Mastectomy with and Without Irradiation

Presenter: Robert Kuske, MDAffiliation: Ochsner Clinic/Tulane University School of Medicine, New Orleans, LA

Background:The prognostic implications of extracapsular extension (ECE) in breast cancer with axillary lymph node (ALN) disease is debatable. It has not been conclusively demonstrated that having ECE in positive ALNs is an indication alone for radiation therapy of the regional lymph nodes. Recent randomized data from post-mastectomy trials have demonstrated a decrease in survival in patients with 1 - 3 positive ALNs with the addition of ECE versus no ECE. Post-mastectomy radiation therapy with the regional lymph nodes addressed equalized the survival in the two subsets.

The primary site of locoregional failure was the chest wall in patients who received no or suboptimal radiation therapy (0 - 44.9Gy) when ECE was present versus when it was absent. This discrepancy is significant only for those with 1 - 3 ALNs positive. Those who have 4 or more positive have a poor locoregional control regardless of the ECE status.

There was no difference in axillary recurrence rates based on ECE status.

Survival was trending to be better in those without ECE, though not significantly.

Post-mastectomy radiation therapy does seem to have a trend in improving survival and locoregional control in those who have ECE as was known from the prior randomized trials.

Arm lymphedema was also significantly increased with the presence of ECE.

Clinical/Scientific Implications:

The presence of ECE in a small number (1 - 3) of ALN positive appears to influence locoregional recurrence rates and survival, though not significantly.

Chest wall is the primary site of failure.

ECE is associated with an increase in the rate of arm edema, with or without radiation therapy.